The purpose of IVF is to:
- By pass the fallopian tube where fertilization normally occurs, so that we can overcome tubal factor if it is one of the factors causing infertility.
- IVF / ICSI can also bypass mechanical factors, sperm defects like acrosome defect or oocyte defects like zona pellucida being too thick. With IVF/ICSI, subtle hormonal defectsget corrected and endometrial receptivity improves. Unexplained infertility may be due to one of the above factors and may get corrected by IVF/ICSI.
- In the natural course, the follicle ruptures when the egg is mature thus releasing the egg, this egg is picked up by the fallopian tube which propels it forwards to the ampullary part(outer one third ) of the tube where fertilization happens. The sperms which are deposited in the vagina have to travel up all the way to the uterus and from there into the tube where the fertilization happens. This is a microscopic process & cannot be documented by sonography or any other tests. This process of fertilization in IVF is done in the laboratory and it is ensured that fertilization happens.
- By removing the eggs we can know the quality of eggs which otherwise cannot be judged.
- In male factor infertility, there might be an inherent weakness in even the normal looking sperms. These sperms cannot fertilize the egg. By doing ICSI, it is made sure that the sperm reaches inside the egg and chances of fertilization are maximized. By, ICSI it is ensured that fertilization of egg happens with the best quality sperm
What is the success rate of IVF/ICSI?
The carry home baby rate is around 30-35%, depending on various factors, which is quite high as compared to almost no hope without IVF/ICSI.
- Age of women
- Pre IVF evaluation & treatment
- Quality of gametes (eggs and sperms ) & embryos
- Number of embryos transferred.
The higher success rates are achieved by meticulous pre IVF evaluation & counseling the couple for the treatment available to them.